DumpIt is a compact portable tool which makes it easy to save the contents of your PC's RAM.
It's a console utility, but there's no need to open a command line, or master a host of cryptic command line switches. Instead, all you do is double-click the program's executable (a tiny 203 KB), press "Y" to confirm that you're "sure you want to continue" - and that's it, DumpIt will save the contents of RAM to a file in DumpIt's current folder.
Of course this may take a while, especially if you've a lot of RAM. DumpIt will save your entire 3GB user address space on a 32-bit Windows system, and the contents of your entire installed RAM on a 64-bit system, so this isn't going to happen in a second or two. Be patient, though, and the DumpIt window will alert you when the process is complete.
What then? Let's say you've been working on the text of an important presentation in a program which has locked up. Dump the RAM to disk, use something like the hex editor HxD to open the file, and you can search for a phrase which you know was in the text. With any luck you'll find it (we tested this with Word 2010 and it worked just fine), and while you won't be able to copy and paste the text from RAM, or easily extract images or binary data, you can at least read it and retype the text elsewhere.
Alternative, MoonSols Windows Memory Toolkit can take a memory dump and convert it into a form which can be analyzed by Microsoft Windows Debugger, which may (for example) help you to figure out why your troublesome program locked up in the first place. Read more at the MoonSols site.